1. Field of the Invention
The present invention generally relates to a package structure and a manufacturing method thereof. More particularly, the present invention relates to a microelectromechanical system (MEMS) package structure and a manufacturing method thereof.
2. Description of Related Art
Microelectromechanical system (MEMS) is a microelectromechanical device fabricated in a microminiaturized package structure, and the fabricating technique thereof is quite similar to the technique of fabricating integrated circuits (ICs). However, interactions, for example, about mechanics, optics, or magnetic force between the MEMS device and surrounding environment are more than that of the conventional IC.
The MEMS device may include micro-sized electromechanical components (for example, switches, mirrors, capacitors, accelerometers, sensors, capacitive sensors, or actuators etc.), and the MEMS device may be integrated with the IC in a manner of single block, thereby greatly modifying insertion loss or electrical isolation effect of the overall solid-state device. However, in the macroscopic world of the entire package structure, the MEMS device is extremely fragile and may be impacted by slight static electricity or surface tension at any moment to cause failure. Therefore, in order to prevent the MEMS device from contaminations or damages, currently, the MEMS device integrated with the IC in a manner of single block is sealed in a space between the base and the cover by glue. However, glue may crack and occur the outgassing phenomena easily in the high temperature and high humidity environment, so that the moisture may permeate into the space between the base and the cover easily after using a period of time in high temperature and high humidity environment, thereby affecting the normal operation of the MEMS device.